Prior art needle penetrable and laser resealable containers include thermoplastic elastomer (“TPE”) stoppers or portions of stoppers that are needle penetrable to needle fill the containers with a product, and are thermally resealable at the resulting needle holes by applying laser radiation thereto to hermetically seal the product within the containers. One of the drawbacks of such TPE stoppers is that they can be difficult to use with fat containing liquid products, such as infant or baby formulas, or other milk-based or low acid products. For example, many such TPE materials contain leachables that can leach into the fat containing product, or otherwise can undesirably alter a taste profile of the product.
Conventional containers and systems for aseptically filling containers with fat containing liquid products, such as infant or baby formulas, or other milk-based or low acid products, employ a container having an open mouth and a screw cap or other type of cap that is secured to the open mouth after aseptically filling the container with the product. In many such systems, the open containers are pre-sterilized by flushing the interior and exterior surfaces of the open containers with a fluid sterilant, such as peroxide vapor or vaporized hydrogen peroxide, to sterilize the food contacting surfaces. Then, the containers are flushed with heated sterile air in order to re-vaporize any fluid sterilant that condenses on the container surfaces and to flush away the sterilant. After flushing with heated sterile air, the open containers are filled through the open mouths of the containers with the desired product, and after filling, the containers are capped to seal the product within the containers. Typically, the sterilizing, flushing, filling and capping processes are all performed within the same sterile zone of the filling system.
One of the drawbacks of this type of filling system is that it can be difficult to remove all of the fluid sterilant from the interior surfaces of the containers, thus leaving sterilant residue, such as hydrogen peroxide; within the containers and thereby contaminating the product filled into the containers. If the level of residue is sufficiently high, the product must be discarded. Alternatively, the sterilant residue can negatively affect the taste or taste profile of the product.
Another drawback of such prior art systems is that because the sterilizing, flushing, filling and capping processes are all performed within the same sterile zone, the apparatus forming the sterile zone tends to be relatively large and complex. Moreover, because the product is open filled (i.e., poured into the open mouths of the containers), the product is not as well contained within the sterile zone as otherwise desired, thus creating hygiene problems within the sterile zone. Such apparatus can require cleaning more frequently than desired due, for example, to the collection of sterilant and/or product residue within the sterile zone. Cleaning such large and complex apparatus can result in substantial down time and expense. As a result, such prior art systems can have undesirably short run times between cleaning and sterilization of the sterile zone. Yet another drawback of such systems is that because they sterilize the packaging, fill and seal apparatus all within the same enclosure and sterile zone, if any part of the system goes down, the entire system must be subjected to clean in place (“CIP”) and sterilize in place (“SIP”) procedures prior to re-starting, which can further contribute to substantial down time and expense.
Yet another drawback of such prior art systems is that the containers are filled immediately prior to capping resulting in poor closure seals due to the presence of wet product at the sealing surfaces or interfaces.
Another drawback of such prior art systems is that in many cases product must be sterilized after filling by employing a retort process that can undesirably alter the taste of the product.
Accordingly, it is an object of the present invention to overcome one or more of the above-described drawbacks and disadvantages of the prior art.